(a) Field
The embodiment of the present inventive concept relates to a liquid crystal display and a method for manufacturing the same.
(b) Description of the Related Art
As a display device, a flat panel display may be used. As the flat panel display, various display devices such as a liquid crystal display, an organic light emitting display, a plasma display, an electrophoretic display, an electrowetting display, and the like may be used.
The liquid crystal display, which is one of the most widely used flat panel displays, includes two sheets of display panels on which electrodes are formed and a liquid crystal layer interposed therebetween. The liquid crystal display displays an image by applying a voltage to the electric field generating electrodes to generate an electric field on the liquid crystal layer and consequently, determining an orientation of liquid crystal molecules in the liquid crystal layer and controlling polarization of incident light.
One that is currently and mainly used among the liquid crystal displays is a structure in which electric field generating electrodes such as pixel electrodes, common electrodes, and the like are formed in each of the two display panels. Among these, a structure is mainly used in which a plurality of thin film transistors and the pixel electrodes are arranged in a matrix form on one display panel (hereinafter, referred to as ‘thin film transistor display panel’) and color filters of red, green, and blue are formed on the other display panel (hereinafter, referred to as ‘common electrode display panel’) and front surfaces of the color filters are covered by the common electrode.
Since the above-mentioned liquid crystal display has the pixel electrodes and the color filters that are formed on different display panels, it is difficult to perform an accurate alignment between the pixel electrodes and the color filters, thereby causing alignment error. In order to solve the above-mentioned problem, a structure in which a light blocking member is formed on the same display panel as the pixel electrodes and the thin film transistor has been proposed. In this case, the color filter may also be formed on the same display panel as the pixel electrodes.
An interval between liquid crystal layers between the two display panels is referred to as a cell gap, wherein the cell gap has an effect on overall operation characteristics of the liquid crystal display such as response speed, contrast ratio, angle of view, luminance, uniformity, and the like. If the cell gap is not constant, a uniform image is not displayed across the entire screen, thereby causing image quality degradation. Therefore, in order to maintain a uniform cell gap across the entire region on the substrate, one of two substrates is provided with a spacer. As the above-mentioned spacer, a column spacer (CS) has been well used.
For process simplification, the light blocking member such as a black matrix and the spacer may be simultaneously formed. In order to simultaneously form the light blocking member and the spacer, it is required to form a multi-step in the light blocking member and the spacer forming material.
Conventionally, the light blocking member and the spacer are formed simultaneously by using a multi-tone mask having areas of different light transmittance characteristics. However, since it is difficult to manufacture the multi-tone mask, cost for manufacturing the liquid crystal display is increased. Moreover it is difficult to form a sub column spacer along with the light blocking member and the main column spacer using the multi-tone mask.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the inventive concept and therefore it may contain information that does not form the prior art.